Several recent initiatives have emphasized the importance of developing and testing new technologies to measure patient-reported outcomes (PRO). PRO measures for asthma can be substantially improved using item response theory (IRT), and competing objectives of more practical and more precise assessments can be achieved over a wide range of severity levels using computerized adaptive testing (CAT), which matches questionnaire items to each patient's level. If more available, such information could complement asthma management plans, enhance patient-caregiver communication, and improve clinical decision-making. Among the limiting factors is the impracticality (respondent burden) of today's HRQOL measures. Short-forms (e.g., SF-36(r), AQLQ) are more practical, however, "ceiling" and "floor" effects limit their ranges and they lack the precision to detect changes in individual patient scores. In Phase I, we developed and piloted a prototype Internet-based assessment (ASTHMA-CAT) that combines asthma impact, asthma control, and generic HRQOL measures in one "seamless" administration, and displays results in tandem in a single user-friendly aggregate (or group-level) report. Results from a pilot test of the ASTHMA-CAT showed that the dynamic assessment achieved almost as precise score estimation with far less respondent burden than the full-length survey, and discriminated well between mild, moderate, and severe asthma. Patients and providers positively evaluated the ASTHMA-CAT assessment and report. The aims for Phase II are to: (1) evaluate items from our current asthma bank for psychometric performance and clinical relevance, and calibrate item enhancements by collecting and analyzing responses from large samples of adults varying in asthma severity;(2) build a completely functional and comprehensive ASTHMA-CAT system with centralized data capture, scoring, and "real time" feedback reports, and evaluate its psychometric performance through data simulation studies;(3) conduct a longitudinal prospective field study of the ASTHMA-CAT to demonstrate its responsiveness, reliability, and construct validity;and to document the comparability of differing modes of administration (e.g., paper and pencil, tablet PC, Internet);(4) evaluate the ASTHMA-CAT's potential for use in remote self- management;and (5) foster the ASTHMA-CAT's integration into clinical practice through comprehensive documentation and development of educational materials. The goal of this effort is an efficient, less burdensome asthma PRO monitoring system with demonstrated evidence of its administrative feasibility, reliability, validity, and responsiveness. If successful, the ASTHMA-CAT system will offer streamlined data capture, processing, and "real time" reporting features;will produce valid and comparable scores across multiple modes of administration;and will provide useful interpretation guidelines to facilitate its routine application in care management. Public Heath Relevance: The ASTHMA-CAT will provide a comprehensive and precise, yet practical, patient-based assessment valid for routine monitoring of asthma impact, asthma control, and generic HRQOL outcomes across a variety of settings. It will yield meaningful and useful results to inform clinical decision-making and improve care management.